My design is 2.5Ghz, so via length is critical. Sean James PCB Designer Telecast Fiber Systems, Inc. 102 Grove Street Worcester, MA 01605 (TEL) 508.754.4858 x33 (FAX) 413.541.6170 ----- Original Message ----- From: "Mike Reagan" <[EMAIL PROTECTED]> To: "Protel EDA Forum" <[EMAIL PROTECTED]> Sent: Tuesday, November 27, 2001 12:39 PM Subject: Re: [PEDA] Vias & trace length
> > > > Is there any way to get Protel to add vias to an overall trace length? Ex. A > via going from top to bottom thru an .062" board would add .062" to a total > trace length (PCAD/ACCEL does this). > > Sean, > I don't think .062 inch for any digital signal under 500 mhz makes any > difference. The actual capacitance of the via will pose more of a problem > than the trace length. Actual measurements made by Bill Brooks > www.ultracad.com and contributing editor to PCD magazine shows no relevant > impedance changes with vias placed in a trace. There are little hic-cups in > the impedance but it really doesn't change much. I wish protel would give > me a calculation of the capacitance with the via included. A trace length > is irrelevant unless it approaches a critical length for the signal, but > loss can become a bigger factor. > Question; Why don't you use Acell PCAD? personally I think it sucks > > > Mike Reagan > EDSI > Frederick MD > * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/[email protected] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
